1. Field of the Invention
The invention relates to a driving device for a scanner, more particularly to a driving device that enables stable driving movement of an image sensor carriage in a scanner.
2. Description of the Related Art
Referring to FIGS. 1 to 3, a conventional scanner is shown to include a base 11, an elongate metal guide rod 12 disposed in the base 11 and extending in a first direction (A), an image sensor carriage 14 extending in a second direction (B) transverse to the first direction (A), movable along the guide rod 12, and having an image sensor 13 mounted thereon, a driving unit 15 for driving the image sensor carriage 14 to move along the guide rod 12 in the first direction (A), and a glass cover 16 to cover the base 11.
It is desirable to prevent wobbling of the image sensor carriage 14 relative to the guide rod 12 while the image sensor carriage 14 is driven by the driving unit 15 to move in the first direction (A), as shown in FIG. 2, so as to avoid deterioration of the scanning quality. Moreover, it is desirable to reduce the resistance to movement of the image sensor carriage 14 along the guide rod 12 for efficient power consumption.